The great majority of ancient Egyptian (Ptolemaic) bronze coins shows a head of Zeus on the obverse rather than a portrait of one of the Ptolemaic kings that would indicate the reigning authority. The reverses predominantly show either one or two eagles together with the legend ΠΤΟΛΕΜΑΙΟΥ ΒΑΣΙΛΕΩΣ (i.e., Ptolemy King, in Greek). Since every Ptolemaic king from 305 to 30 BC had the same name, this legend, like the Zeus head, is not helpful in determining when a coin was produced.
However, the two coins illustrated below do not show any portrait or name that would immediately indicate any specific king or queen. If attributions are possible, they must be based on aspects of the coins other than the obverse image of Zeus or the reverse legend for King Ptolemy.
Although her name or portrait is not present on these coins, there are fortunately other features that lead to their attribution to Cleopatra. To clearly see these features --
Click on Show useful feature of first coin and
Click on Show useful feature of second coin
So-called “control marks”, such as on each of these two coins, are often useful in attributions. These were placed on Ptolemaic coins for several reasons: in order to indicate a source (i.e., a mintmark), a sequence of production (i.e. a period of time) or an official in charge of production (i.e., a monogram).
With the above coins the control marks are, respectively, structured as follows --